Distribution cabinet

ABSTRACT

A distribution cabinet ( 1 ) for accommodating weak-current distribution installations, in particular for arranging outdoors, having  
     a base box ( 2 ),  
     an outer cabinet body ( 3 ) with at least one door ( 4 ),  
     a cabinet cover ( 5 ), and  
     an inner installation frame ( 6 ),  
     the installation frame ( 6 ) being made up of profile sections ( 50 ), of which the cross-sectional shapes has two insertion pockets ( 51   a,b ), of which the insertion directions ( 52   a,b ) run at right angles to one another.

I. APPLICATION AREA

[0001] The invention relates to a distribution cabinet which is usuallyset up outdoors and accommodates the distribution installations forweak-current systems, for example telephone systems, with associatedpower-supply devices and cable-terminal/-connection devices for acertain area.

II. TECHNICAL BACKGROUND

[0002] Nowadays—in addition to having sufficient structural stabilityand resistance to vandalism, etc.—such distribution cabinets have tosatisfy further requirements, for example excessive electromagneticradiation must not be emitted to the surroundings, and, for use inwarmer countries in particular, the temperatures in the interior of thedistribution cabinet must not rise to too high a level, despite theheat-emitting electrical subassemblies accommodated there, nor must theydrop to too low a level.

[0003] Such distribution cabinets are basically produced either frommetal or from plastic, plastic combining the advantage of less expensiveproduction with the advantage of an electrically non-conductivematerial, with the result that, even in the case of unplanned contactbeing established between the housing of the distribution cabinet and anelectrical component, there is never a risk of a person who touches thehousing from the outside receiving an electric shock.

[0004] As far as the sufficient cooling capability of such distributioncabinets is concerned, it is already known for cooling to be effected byair circulation. For this purpose—up until now only in the case ofdistribution cabinets consisting of sheet steel—the body is ofdouble-walled configuration, it being possible for the ambient air tocirculate in the interspace between the walls, that is to say to pass inat the bottom and to pass out at the top, as a result of which, on theone hand, the interior is heated up by the sunlight and, on the otherhand, heat is dissipated on the inner wall, which are heated up by theelectrical subassemblies in the main chamber.

[0005] Such a double-walled construction is indeed theoreticallypossible even in the case of distribution cabinets produced fromplastic. However, on account of the greater wall thicknesses which arenecessary in this case, and of the outer and inner dimensions beingpredetermined by standards in the various countries, this would resultin excessively small free spaces on the inside and overall dimensions onthe outside.

[0006] In addition, it is extremely important for such distributioncabinets not to exceed the admissible maximum value of electromagneticradiation emitted to the outside, that is to say for the EMC(electromagnetic compatibility) to be ensured.

III. DESCRIPTION OF THE INVENTION

[0007] a) Technical Object

[0008] The object of the present invention is thus to provide adistribution cabinet and an assembly kit for producing such adistribution cabinet, the distribution cabinet consisting at leastpartially of plastic and nevertheless providing sufficiently goodshielding against electromagnetic radiation, on the one hand, and asufficient cooling capability, on the other hand.

[0009] b) Solution of the Object

[0010] This object is achieved by the features of claim 1. Advantageousembodiments can be gathered from the subclaims.

[0011] Up until now, distribution cabinets produced from plastic usuallycomprised a base box, which was usually open on the top side and also onthe underside, since the underground cables were introduced into thebase unit, a body, which was positioned on the base and on which one ortwo doors or flaps for opening the body were provided, for the purposeof installing or maintaining and checking the electrical units in theinterior of the body, and a cover protecting the body, open on the topside, and one upward against rain and other influences, and usuallypositioned in a sealed manner.

[0012] It was additionally possible for the body to have a base plate asan integral or separate component which—apart from the through-passagesfor the cables—separated off the main chamber in the interior of thebody from the base chamber.

[0013] A distribution cabinet according to the invention may be producedfrom these known components by the addition of an installation framewhich is made up, in particular, of deflected sections of an endlessprofile. The specific integration of the profile makes it possible, onthe one hand, to simplify the assembly to forma—three-dimensional—installation frame to a very considerable extentand, in addition, to facilitate the optional fitting of EMC shieldingand/or the production of a double-shell wall of the distribution cabinetfor ventilation and cooling purposes.

[0014] The profile here—as seen in cross section—preferably has anapproximately rectangular cross section, in particular two continuousouter surfaces running at right angles to one another. The other two,inwardly oriented outer surfaces each have an insertion pocket which isopen on the outside and is intended for the insertion of insertionpanels, of which the insertion direction is arranged parallel to thecontinuous outer surfaces and which are preferably also arranged as faras possible in the outward direction in the profile side surfacethereof.

[0015] This preferably produces a cross-sectionally continuoushollow-chamber profile in the inner corner of the profile, thisstabilizing the profile, in particular when the cross-sectional shape ofthe hollow chamber has one or more recesses, preferably directedoutward.

[0016] In the case of essentially constant wall thicknesses beingprovided, these recesses are produced, on the one hand, by the alreadymentioned insertion pockets and, on the other hand, by at least one,preferably precisely one further pocket 57, which extends parallel toone of the insertion pockets and is open in the outward direction, buthas undercuts, preferably arranged symmetrically in relation to oneanother in both flanks. These undercuts are used for arranging embracinga groove nut therein.

[0017] This configuration makes it possible, on the one hand, for threesuch profile sections to be connected to one another relatively easilyto form a three-dimensional corner connection:

[0018] This takes place by two profile sections being cut to length andmitered and positioned one against the other. This three-dimensionalcorner connection is secured by an angle which is pushed, by way of itslegs, into the open ends—from the miter—of the undercut of the pocketand is fixed there by means of, for example, clamping screws or else isfastened on the outsides of the two profile sections.

[0019] Since this angle or a groove nut has a threaded bore in thedirection of the third, as yet missing, angle profile, this third anglecan be positioned flush on the first two angles, which are alreadyconnected to one another, and fixed against the angle or the groove nutby means of a clamping screw, which is arranged in the longitudinaldirection of the pocket, and within this pocket of the third profile,and can be screwed into the threaded bore of the angle or of the groovenut. This clamping screw is secured in its longitudinal direction in thethird profile with the aid of a transversely running threaded boltarranged in a transverse bore or with the aid of other means.

[0020] All of the additional elements necessary for the cornerconnection are located within the cross section of the threecorner-forming profile sections.

[0021] It is possible for the profile configuration, furthermore, to beused very easily in order to complete the installation frame, formedfrom the profile sections, in that appropriately cut-to-size insertionpanels are inserted into the insertion pockets, with the result that therespective side of the installation frame is a more or less closed side,that is to say when the panels are continuous panels which do not haveany through-passages.

[0022] If the EMC shielding is to be achieved by means of the insertionpanels, these panels will consist of metal or will have metalliccomponents as a coating or addition, if the panels themselves consist ofplastic. In addition, an EMC seal is then preferably positioned betweenthe edges of the panels and the grooves of the insertion pocketsaccommodating them.

[0023] These panels, however, may also serve for forming the inner shellof a double-shell distribution cabinet, the outer body forming the outershell. The air space provided therebetween serves for ventilation andcooling purposes in that—since the air space is open at the top andbottom—on account of the chimney effect air, preferably from thesurroundings, flows in at the bottom and flows out at the top and istransported away in the interspace, in particular from the outer wall,which is irradiated by the sun. For reasons of cost and for heating-upreasons, the outer wall will preferably consist of plastic here.

[0024] It is thus possible, with the aid of a corresponding assemblykit, for the installation frame, which is located in the interior of theouter body, to be used not just for arranging the electrical components,but also for optional fitting with EMC shielding, with a second, innershell for the purpose of a ventilated double-shell cabinet housing, italso being possible for both these things to be functionally combined bycorresponding panels.

[0025] Irrespective of this, a further improvement may be provided bycompletion by means of further components, it being the case inparticular—in contrast to the previously described, knowncomponents—that additional parts for supplementary purposes, rather thanstill having to consist of plastic, [lacuna] also [lacuna] of othermaterials, for example aluminum or sheet steel, in particular ofhigh-grade steel, be this for reasons of shielding againstelectromagnetic radiation (EMC shielding) or for reasons of thermalconductivity.

[0026] Such an additional part may be formed by a top intermediate part,which is positioned between the top border of the body and the cover,which closes off the top, in particular in a sealed manner in relationto the body. This top intermediate part serves occasionally for heatingpurposes, but mostly for additional temperature reduction in theinterior of the main chamber, that is to say in the interior of thebody, and thus of the installation frame in the this interior is cooledby means of the top intermediate part, to be precise, depending onrequirements, in different ways:

[0027] On the top intermediate part, which, in addition to a borderrunning all the way round the outside, also has a false floor, whichpreferably seals the main chamber of the body in the upward direction,one or more bottom cooling structures may be fastened on the undersideof the false floor, that is to say also, in certain circumstances, alsoprojecting some way into the main chamber of the body. These coolingstructures extract heat from the air circulating in the interior of themain chamber as it passes along beneath the ceiling, that is to say theunderside of the false floor, in that said cooling structure—usually aribbed structure—gives off its heat, by heat conduction, to the interiorof the false floor, which is likewise a good heat conductor, thestructure being fixed to the false floor or even possibly integrallyformed therewith.

[0028] The top intermediate part itself, rather than being sealed, aboveits false floor, in the direction of the surroundings, has openings, forexample slots which are arranged in the side borders and allow ambientair to pass in and out, said ambient air dissipating heat as it passesalong the top side of the false floor. This can be enhanced if, in turn,a top cooling structure is arranged on the top side of the false floor,preferably at the same location as the bottom cooling structure. It isalso possible for the top and bottom cooling structures to be formedintegrally with one another and to be arranged in a sealed manner in acorresponding through-passage of the false floor.

[0029] This effect is more pronounced as the surface area of the coolingstructure increases, for which reason said cooling structure willusually cover more than half, for example two thirds or three quartersof, the surface area of the false floor.

[0030] In order to optimize the passage of air along the cooling ribs onthe top side of the false floor, it is advantageous, in particular, forthese cooling ribs to be arranged—as seen in the plan view of the topside of the top intermediate part—in particular radially in star form,for example extending away from the center of the false floor, and forthe region around the geometrical crossover point of these radiallyrunning cooling ribs to be left free in order for a passive, that is tosay non-driven, radial-flow impeller to be arranged there such that itcan be rotated about a vertical axis. The radial-flow impeller in thiscase has blades which are curved arcuately in plan view in particular.

[0031] By virtue of such an arrangement—in particular if a sufficientnumber of ventilation slots of a sufficient size are provided all theway round the side borders of the top intermediate part, level with thecooling ribs and/or the fan—the impeller is driven by wind blown intothe ventilation slots from the outside, and thus, on the opposite sides,forces air radially outward between the cooling ribs, as a result ofwhich outside air constantly passes over a particularly large number ofcooling ribs.

[0032] In addition, a functional opening is optionally arranged in thefalse floor, it being possible for said opening to be closed firmly by afunctional cover, or for the functional cover thereof to be opened byhand or else automatically, namely when a certain threshold temperaturein the interior of the main chamber is exceeded, or for said functionalopening to serve instead, or in addition, for accommodating furthercomponents.

[0033] The functional parts which are inserted into the functionalopening—it being immaterial here whether the functional parts extendmore above or beneath the false floor in a vertical direction—may be aninserted air filter with an EMC filter, for passive cooling of the mainchamber with the functional opening open, or else an active,electrically operated fan, which then extracts warm air by suction,through the functional opening, from the interior of the body, or elsethe above-described passive fan, which is then preferably placedvertically above the false floor, forces [lacuna] into the region abovethe false floor of the top intermediate part and, through the openingsprovided there, into the surroundings.

[0034] It is also possible to insert an air/air heat exchanger, whichpreferably has open primary and secondary circuits in each case, airfrom the main chamber, that is to say from the body, flowing through onecircuit, while air from the region above the false floor, that is to sayambient air from the outside, flows through the other circuit. The airfrom the main chamber is thus always separated from the ambient air andsealed from the latter, with the result that the penetration ofcontaminants is prevented.

[0035] The flow of the two types of air through the respective opencircuits of the heat exchanger may be assisted on one or on both sidesin each case by driven, preferably electrically operated, fans. It isalso possible for just one of the two circuits to be provided, while theother circuit is absent, and the other type of air just flows over acorrespondingly large outer surface area of the heat exchanger and feedsand dissipates heat via conduction.

[0036] Another additional part may be formed by an—in particularspecifically configured—installation frame in the interior of the body.The installation frame is preferably a self-supporting frame which ismade up of aluminum profiles, runs in the vicinity of the inside of thebody, has a high level of stability, and on which the electricalsubassemblies are fastened and connected to the cables.

[0037] For this purpose, the installation frame is preferably ofcuboidal configuration with open side surfaces, the profiles runningalong all the edges of the cuboid. It is preferable here for thehorizontally running transverse struts at the top, rear edge—as seenfrom the front doors of the body—to be offset downward, in order for itto be possible for necessary installations to be better fixed there.

[0038] In the front surface of the installation frame, a rectangular,vertically upright two-dimensional frame is additionally provided as amounting rack, which is arranged on the top and bottom front transversestruts of the installation frame such that it can be displaced in thehorizontal direction. The electrical subassemblies are fastened on saidmounting rack and can thus be positioned in accordance with the positionof the cables, running in from beneath, by virtue of the mounting rackbeing displaced. It is also possible for more than one such mountingrack to be provided in the installation frame.

[0039] Otherwise, all the outer surfaces of the installation frame areopen, and are not closed over the surface area. In addition, thedistribution cabinet has EMC shielding, which can be realized indifferent ways, but always has to consist of a material which does notallow electromagnetic radiation to pass through.

[0040] This material may be added, in a sufficient concentration, to theplastic of which the body and/or the doors and/or the cover and/or thebase, etc. consist, or the abovementioned plastic parts may be providedon the inside with a coating which contains this material, or consistsof this material, or the main chamber is lined with a woven fabric ofthis material, or with metal sheets or perforated metal sheets of thismaterial, at least on its peripheral sides, preferably also at thebottom and top.

[0041] The fastening in the two last-mentioned cases may be providedeither on the insides of the body or of the doors or on the outsides ofthe installation frame.

[0042] It is particularly advantageous here for the installation frameto be fastened not on the body but exclusively on the base, or on thebottom intermediate part positioned on the base, and, in addition, forno undercuts—as seen in the transverse direction—to be permitted betweenthe installation frame and body.

[0043] This is intended to allow existing distribution cabinets to beconverted without operation being interrupted in that the electricalcomponents which are fixed and connected in the installation frameremain there and, in addition, need not be disconnected, but the coverand body can nevertheless be raised off in the upward direction.

[0044] This is often necessary in order to exchange the damaged body, orin order to exchange the body for another type of body, for example anEMC-proof body, or in order for it to be possible to install EMCshielding between the outside of the installation frame and the insideof the body and then to place the old body in position again.

[0045] A further additional part is formed by the bottom additionalpart, which is positioned between the base box, which is open at thetop, and the bottom border of the body or of the installation frame.

[0046] This bottom intermediate part is likewise of tray-like designagain, with a false floor and a peripheral border, and openings arelikewise provided again in order to allow ambient air to penetrate intothe region beneath the false floor.

[0047] The configuration selected here is preferably one in which, inthe top region of the base box, the outer wall of the latter is set backinward, and a horizontal spacing, serving as an opening, thus remainsbetween said wall of the base box and the outer border of the bottomintermediate part, with the result that said opening cannot be seen fromthe side or laterally at the top. The same principle can also be appliedfor the top intermediate part.

[0048] The false floor of the intermediate part, rather than beingcompletely closed, has a plurality of cable through-passage openingsdistributed over its surface, it being possible for said openingsoptionally to be closed by covers which have a sealing action, on theone hand, against contamination, but also against electromagneticradiation. For this reason, the bottom intermediate part and the coversclosing the cable through-passage opening, in turn, is also producedfrom an EMC-shielding material, for example aluminum.

[0049] In addition, it is also possible for the false floor of saidbottom intermediate part to have one or more functional openings, whichmay analogously serve the same purposes, and thus for the installationof the same functional parts, as have been described with reference tothe top intermediate part.

[0050] For this reason, it is possible for the false floor to be locatedeither in the top height region of the vertical extent of said bottomintermediate part, if said functional parts are positioned beneath thefalse floor, or the other way round—and this is the preferredembodiment—in the bottom region of the vertical extent, in order toprovide space, above the false floor, for arranging such functionalparts as a fan, which, for power-supply purposes, has to be connected tothe electrical subassemblies of the main chamber and, in addition,requires space.

[0051] By virtue of adding one or more of the above-mentioned additionalparts or additional measures to the already known components, it ispossible to produce, depending on the use purpose, the specificdistribution cabinet from this assembly kit.

[0052] c) Exemplary Embodiments

[0053] An embodiment according to the invention is described in moredetail by way of example hereinbelow with reference to the figures, inwhich:

[0054]FIG. 1 shows an exploded illustration of the distribution cabinetaccording to the invention,

[0055]FIG. 2 shows an illustration of a vertical section through the toppart of the distribution cabinet,

[0056]FIG. 3 shows an illustration of a vertical section through thefunctional opening of the top intermediate part and through a functionalpart inserted there,

[0057]FIG. 4 shows another functional part inserted at this location,

[0058]FIG. 5 shows a vertical section through the finished distributioncabinet,

[0059]FIG. 6 shows illustrations in detail form of the top intermediatepart,

[0060]FIG. 7 shows the bottom intermediate part,

[0061]FIG. 8 shows a plan view of another top intermediate part,

[0062] FIGS. 9 show the installation frame comprising profile sections,and

[0063]FIG. 10 shows an illustration in detail form of the cross sectionof the profile sections.

[0064]FIG. 1 shows the individual components which make up thedistribution cabinet—in the non-fitted-out state —in an explodedillustration, that is to say drawn apart from one another in thevertical longitudinal direction 10 of the distribution cabinet.

[0065] The base box 2 is a box which is open at the top and bottom andhas walls along the entire periphery, the box, in the installed state,partially projecting from the ground, and the underground electric linesbeing introduced into the distribution cabinet from beneath through saidbox. The front side of the latter can be opened.

[0066] The side-wall outer surfaces which are set back inward in the topend region can be seen here, as is also the case in FIG. 5 inparticular.

[0067] By virtue of the bottom intermediate part 8, which comprisessheet metal, in particular aluminum, being positioned on the base box 2,the outer periphery of said bottom intermediate part being equal to, orslightly greater than, the base box 2, downwardly oriented inletopenings 33 are produced between the bottom edges of the border 32 ofthe bottom tray-like intermediate part 8, said border running all theway round the outside, and the top end region of the base box 2 providedsaid bottom intermediate part 8, rather than resting on the entireperiphery of the top border of the base box 2, only rests on certainsections thereof, for example only in the corner regions.

[0068] These openings for the passage of the ambient air into the mainchamber 26 are necessary, in particular, if air is extracted from themain chamber 26 by suction at some other location, e.g. in the topregion via a top intermediate part.

[0069] For this purpose, it is possible, for example, for the border 32of the intermediate part 8, as seen in cross section, to be ofapproximately U-shaped configuration with the open side orienteddownward, the inner vertical or obliquely vertically running leg thereofthen merging into the horizontal false floor 31 on two or four sides.

[0070] In the low-level false floor 31 of the tray-like intermediatepart 8, it is possible to see the cable through-passage openings 24,which are lined up in a row in the transverse direction—see FIG. 7 inparticular—and can be closed in an EMC-proof and also dust-proof mannerby closure covers—not illustrated. Three functional openings 17 arearranged in a second, parallel row in the false floor 31.

[0071] The body 3, which can be opened and closed on the front side byone or two doors 4, which are only indicated in FIG. 1, is fitted on thebottom intermediate part 8.

[0072] The installation frame 6, which is illustrated therebeneath, islocated completely within the body 3 in the assembled state of thedistribution cabinet, as is illustrated in the section in FIG. 5, and isfixed, preferably screwed, to the base box 2 and to the body 3 via thebottom intermediate part 8, screw connection, moreover, being thepreferred method of connection between all the components of thedistribution box.

[0073] On the sides and on the rear wall, the body 3 has continuouspanel-like walls which are stiffened on the inside by ribs 30, etc., itbeing possible for the body 3 to be in one piece or made up of differentparts.

[0074] The at least one door 4, which like the body 3 is produced fromplastic, namely as in injection molding, in particular by structuralfoam molding, is articulated on the body 3 via hinges and has a lock, inorder to prevent unauthorized individuals from opening it.

[0075] The body 3 is open on the top side and also on the underside, butcan be closed, to the greatest extent, on the underside by a base plate25, which may have cutouts for individual cables which are to be ledthrough, as is indicated in FIG. 1.

[0076] The base plate 25 is used either instead of the bottomintermediate part 8, in order to prevent, in particular, sealing againstpenetrating dust and also to provide EMC shielding, but also in additionto the bottom intermediate part 8, if, for example, the bottomintermediate part 8 consists of plastic and does not provide any EMCshielding.

[0077] In this case, the base plate of the body 3 is designed as EMCshielding.

[0078] The installation frame 6 is located in the interior of the body 3and is dimensioned such that, to the greatest extent, it fills theinterior of the latter. The installation frame 6 comprises a latticeworkof struts which preferably run along the edges of the cuboidal overallcontour of the installation frame 6.

[0079] It is merely the rear top transverse strut 34, which runs in ahorizontal transverse direction 20, which is offset downward, thisconstituting one of four transverse struts 34 located one above theother on the rear side of the installation frame which serves for thefitting of power-supply devices, cable-terminal devices, etc.

[0080] Apart from along the edges, the open side surfaces of theinstallation frame are not provided with additional struts eitherhorizontally or transversely. The same also applies to the front of theinstallation frame. There, a mounting rack 9 in the form of arectangular, two-dimensional, vertical frame is additionally mounted ina displaceable manner in a displaceable manner on the top and bottomtransverse struts of the front side of the installation frame 6 in orderfor it to be possible to change the position, for example in accordancewith the position of the required cables.

[0081] At a later stage—with the distribution cabinet 1 finished and thedoor 4 open—the fitter fastens the electrical subassemblies on saidmounting rack 9 in that the vertical struts of the mounting rack 9 areat a standard spacing apart from one another and have standard fasteningparts or rows of holes 29 for the screw connection of the electricalsubassemblies.

[0082] It is also possible to arrange in the interior of theinstallation frame 6, that is to say in the main chamber of thedistribution cabinet 1, additional electrical units, for example acontrol means, in dependence on the interior temperature in the mainchamber for the cooling—be this active or passive, as will be describedhereinbelow.

[0083] Fitted on the open top side of the body 3 is the top intermediatepart 7, which—like the bottom intermediate part 8—is only a fewcentimeters high, with the result that the bottom and top intermediateparts 7 and 8 together only increase the overall height of thedistribution cabinet 1 by a total of not more than 15 cm in relation tothe state of said cabinet without these intermediate parts.

[0084] The top intermediate part 7 is fitted in a close-fitting manneron the body 3 and is itself, in turn, covered in the upward direction bythe cover of the distribution cabinet 1, said cover being positioned onthe top intermediate part 7.

[0085] The basic construction of the top intermediate part 7 can betterbe seen in FIG. 2, which shows an illustration of a vertical sectionthrough the top region of the distribution cabinet 1.

[0086] It can be seen here that the top intermediate part 7, which onaccount of the thermal conductivity and of the EMC shielding preferablyconsists of aluminum, has a false floor 11 which is enclosed by aperipheral border 12, the false floor 11 here preferably being locatedrather in the bottom height region of the essentially vertically uprightborder 12. The cover 5 is positioned on the top end surface of said topintermediate part 7.

[0087] The right-hand half of FIG. 2 shows a bottom cooling structure 14and a top cooling structure 15 projecting in the upward and downwarddirections from the false floor 11, the cooling ribs of said coolingstructures nevertheless preferably running transversely to the viewingdirection, that is to say in the transverse direction 20 of thedistribution cabinet 1.

[0088] This is based on the idea that air circulates constantly in theinterior of the main chamber 26, that is to say of the body 3, thisbeing driven by the heat-emitting electrical subassemblies which areinstalled there, and are installed in the mounting rack in particular.

[0089] At the location at which these electrical subassemblies arelocated, the air is heated and rises (see FIG. 5), while, in the regionsof the main frame which are remote therefrom, in particular the borderregions, it descends along the inner surfaces of the walls of the body.

[0090] Beneath the bottom end of the main chamber, that is to saybeneath the false floor 11 of the top intermediate part 7, said falsefloor being seated in a close-fitting manner on the body 3, the air thusflows along essentially horizontally, and thus along the cooling ribs 36of the bottom cooling structure 14, which thus extracts heat from theair from the main chamber.

[0091] For this purpose, the cooling structures 14, 15 consist of amaterial which is a good heat conductor, in particular likewise ofaluminum. By virtue of surface-area abutment with, and connection to,the underside of the false floor 11, the bottom cooling structure 14gives off its heat to the false floor 11. Since a top cooling structure15 is installed at the same location, in turn, above said bottom coolingstructure, this top cooling structure, over its entire surface area, inparticular its likewise provided cooling ribs 36, gives off heat to thatair which passes into the interior of the top intermediate part 7 abovethe false floor 11, from the surroundings, via the slots 13 and passesout at some other location again via the analogous slots 13.

[0092] The achieves the dissipation of heat exclusively via thermalconduction from the main chamber 26 into the region above the falsefloor 11 without there having to be an open connection between the twowhich allows the penetration of water or contaminants into the mainchamber.

[0093] For the air to pass in and out, it is possible for the slots 13either, as is illustrated in the left-hand half of FIG. 2, to be formedin the vertically upright border 12 or, as can be seen in the right-handhalf of FIG. 2, covered from the top and to the side, to be produced inthat the border 12 of the intermediate part 7 is set back inward atleast in certain sections in the radial direction, and the outer borderof the cover 5 seated thereabove thus projects further outward, and itis also the case that the cover 5 is seated on the intermediate part 7,and fastened, in particular screw-connected, there, not over the entireperiphery but likewise only in certain sections, and definitely not inthe regions of the set-back border 12.

[0094]FIG. 2 also illustrates a functional opening 17 in the false floor11 in the region alongside the cooling structures 14 and 15, thefunctional opening in FIG. 2 being closed by a functional cover 18,which provides both sealing against penetrating water and contaminationas well as the same EMC shielding as the false floor 11 itself.

[0095] This is provided if the dissipation of heat from the main chamberby means of the abovedescribed coolers 14 and/or 15 is sufficient forthe respective use purpose or use location of the distribution cabinet.

[0096] If additional measures, for example active ventilation of themain chamber 26 or active cooling of the air of the main chamber, isnecessary, the functional cover 18 is removed and the functional opening17 is thus opened up in order for it to be possible to accommodatevarious functional parts here:

[0097]FIG. 2 illustrates, by dashed lines, a functional cover 18′ whichcan be opened and closed, is retained, for example, on one side of thefunctional opening 17 by means of a hinge and can be openedautomatically and with sensor control by means of an electricallyoperated drive 37, for example via a pinion and rack. This allows theheated air from the main chamber which is accumulating beneath the falsefloor 11 to escape upward out of said main chamber, for which purpose itis necessary for cool air to flow in afterward, preferably via the basebox 2 and/or the inlet openings 33, between the base box 2 and bottomintermediate part 8, into the functional chamber 26.

[0098] In order to prevent electromagnetic radiation from passing outthrough the open functional opening 17, and/or moisture or othercontaminants from penetrating through the same, the functional opening17 is closed by means of a dust and moisture filter 22 and of an EMCfilter 23, these both nevertheless being air-permeable.

[0099] Such a combined air/EMC filter 22/23 is depicted in the enlargedillustration in detail form of the functional opening 17 in FIG. 4, inwhich case an electrically driven fan 21, that is to say an impeller,additionally extracts the air by suction in the upward direction fromthe main chamber 26.

[0100]FIG. 3 shows a further possible means, namely a heat exchanger 19,which is seated in the functional opening 17 and is thus connected tothe main chamber 26, on the one hand, and also to the chamber above thefalse floor 11. Here too, the heat exchanger 19 is arranged in a sealedmanner in the functional opening 17, with the result that it is notpossible here for any air to be exchanged between the main chamber 26and the chamber above the false floor 11.

[0101] The heat exchanger from FIG. 3 only has one open circuit, namelyfor the air above the false floor 11, which is forced through lines 28,preferably with the aid of a fan 21′, from one side to the other. Thelines 28 through which this air is moved are, in particular, bent atright angles and extend into the region beneath the false floor 11 andthus down into the main chamber 26. The air from the main chamber 26 canpass over them directly there either in an actively driven manner via afurther fan 21″ positioned there or the air is guided in the mainchamber 26—with or without said fan 21″ in the main chamber—in turn, bypipelines—not illustrated—which are connected for thermal conduction tothe pipelines 28 of the first circuit.

[0102] Instead of the abovedescribed air/air heat exchanger, it is alsopossible to use an air/water heat exchanger, in the case of which,instead of the air being used above the false floor 11, use is made ofwater or some other liquid refrigerant, which then nevertheless has tobe pump-circulated and is cooled, in turn, by the ambient air flowingalong, this passing into the top intermediate part 7 in the region abovethe false floor 11.

[0103]FIGS. 6a and b show, in a perspective illustration and in crosssection, a further variant of a top intermediate part 7. This differs byway of an approximately central functional opening 17 and coolingstructures which are arranged on both sides in this respect, that is tosay two top and two bottom cooling structures 14 and 15. Furthermore,rather than just one row of slots 13 being provided all the way roundthe border 12, two rows 13 a, b are provided one above the other, onerow being located above the false floor 11 and one row being locatedbeneath the same.

[0104] This results in two different possible uses:

[0105] Depending on whether or not the top border of the wall of thebody 3 is installed within the border 12 of the top intermediate part 7such that it butts in a close-fitting manner against the underside ofthe false floor 11 of said top intermediate part, the slots 13 b of saidbottom row ventilate the main chamber 26 directly in the outwarddirection or not.

[0106]FIG. 8 shows a plan view of a top intermediate part 7 which has arectangular outline and is enclosed by a peripheral, upwardly projectingside border 12 in which there are located—preferably verticallyupright—slots 13, which are intended to allow ambient air to pass in andhave the highest possible surface area—preferably more than 50%—inrelation to the overall surface area of the side border 12.

[0107] At one location—preferably in the center—a radial-flow impeller38 is arranged on the false floor 11, which forms the plane of thedrawing of FIG. 8, such that it can be rotate about an axis 40, which islocated perpendicularly to the false floor 11. The blades 39 of theimpeller 38 here are curved arcuately in order, in the case of lateraloncoming flow, always to effect a preferred direction of rotation and,in the direction opposite the direction of oncoming flow, to force theair radially outward.

[0108] Arranged radially around the region of the impeller, andpreferably extending as close as possible to the impeller 38, arecooling ribs 36 which project up from the false floor 11, run radiallyoutward in star form and thus, on the one hand, have the outside airwhich flows against the impeller passing over them and, on the otherhand, on the opposite side, have the air which is forced radiallyoutward by the impeller 38 passing over them, this assisting the coolingof the cooling ribs 36.

[0109] The same design or an analogous design—that is to say radialarrangement of the cooling ribs and a rotatably mounted impeller—may befound on the underside of the false floor 11, the underside not beingvisible in FIG. 8, as in both cases the impellers are preferably notdriven, that is to say are passive, and are only driven by the airflowing against them—beneath the false floor, then, by circulationoccurring there in the interior of the body.

[0110] It is additionally possible for the impeller located above thefalse floor 11 and the impeller located beneath the false floor 11 to beconnected into one another in a rotationally fixed manner via a commonshaft, as a result of which, despite the sealed false floor 11, theimpeller 38 located above the false floor, and driven by the outsideair, assists the circulation in the region beneath the false floor 11,that is to say in the sealed part of the body.

[0111] It is likewise possible—preferably in the region of the impeller38—for one or more functional openings 17 to be arranged for example ascircular openings arranged in star form around the axis of the impeller,in order to provide a through-passage opening for air from the regionbeneath the false floor 11 into the region above the same. In this case,the impeller is designed as a combined axial-flow/radial-flow impeller,in order for the warm air located beneath the false floor 11 to be takenupward by suction in the axial direction of the impeller.

[0112] It is possible here, as has been described above, for thefunctional openings 17 to be sealed by EMC filters, dust filters, etc.and also to be closed by openable covers, in this case on the undersideof the functional openings 17, if there is only one impeller located onthe top side of the false floor 11.

[0113]FIG. 9a shows the installation frame 6 which has been completed toform an inner housing and, with the aid of insertion panels 58 a,b,c,etc. inserted there, is open on all sides apart from the front side(door side) and underside (cable seat). Perforations 64 can be seen inthe insertion panels of the side parts, the perforations serving fordissipating warm air to the outside of the insertion panels (58) andtransporting it away outward in the upward direction by way of the airflowing along there.

[0114] In the finished state, the inner housing, as is illustrated inFIG. 9a, is enclosed by an outer body 3, with a spacing between the two.

[0115] The doors, which close the front side but are not illustrated inFIG. 9a, may likewise be of double-walled design.

[0116] If the insertion panels 58 a,b,c, etc. serve for EMC shielding incontrast, or serve for EMC shielding in addition, perforations 64—independence on the limit values which are to be maintained—will not beadmissible since it is precisely through these perforations thatelectromagnetic radiation could pass out of the inner housing. Since theouter body 3 preferably consists of plastic, the latter does not provideany further shielding for the EMC radiation.

[0117] In the finished state, furthermore, the underside of theinstallation frame 6 is closed by a base plate 25, which is indicated inFIG. 1, to the extent where there are only narrow through-passages therefor the underground cables which are to be introduced from beneath, butotherwise EMC shielding is provided.

[0118]FIGS. 9 and 10 shows, in a horizontal section and a perspectiveillustration, the corner connection produced from three profile sections50 a,b,c. The cross section of the profile, which can also be seen inFIG. 9c, can better be seen in FIG. 10: the profile is rectangular,virtually square, in cross section, and has two continuous outersurfaces 53 a, 53 b adjacent to one another. Insertion pockets 51 a,bare arranged on the inside of these two outer surfaces, for theinsertion of correspondingly dimensioned insertion panels 58 a,b, as canbetter be seen in FIG. 9c.

[0119] The insertion direction of these insertion pockets is parallel tothe continuous outer surfaces 53 a,b and, correspondingly, theseinsertion directions 52 a,b are likewise at right angles to one another.

[0120] A further pocket 57 is additionally arranged on one of thenon-continuous outer sides, that is to say with an insertion directionparallel to the insertion direction 52 a of the one insertion pocket 51a. This additional pocket 57, in its flanks, has symmetrically providedundercuts 57 a,b, which is used for positioning and bracing aconventional groove nut 65, as is illustrated by way of example in FIG.9b.

[0121] The free space still remaining within the profile cross sectionbetween the outer surfaces 53 a,b, and the walls of the latter, and thepockets 51 a,b and 57 forms, in the corner region, a hollow chamber 55which is continuous on all sides in cross section, and is thus verytorsionally rigid, and has additional recesses 56 a,b, whichadditionally increases the rigidity. In this case, one recess 56 bprojects between the inner end of the pocket 57 and the side of oneinsertion pocket 51 b.

[0122] The perspective illustration of FIG. 9b shows the production of acorner connection:

[0123] First of all two profile sections 50 a,b are mitered andpositioned one against the other by way of said miters and connected.The miter here is arranged such that the opening of the pocket 57 withthe undercuts 57 a,b is located in the plane defined by the two profiles50 a,b, which are positioned at an angle one against the other.

[0124] The connection is produced by an angle which fits into theundercuts 57 a,b and, by way of its free ends, is pushed into the freeends of the mitered undercuts 57 a,b, as is known per se. However, incontrast to the known solutions, the angle, rather than necessarilyhaving to be braced separately against the groove base of the pocket 57by means of clamping screws, has a threaded bore 63 precisely along itsangle bisector, that is to say in the corner.

[0125] It is also possible, however, for the angle to be fastened on theoutside of the two profile sections positioned one against the other ata miter joint, said outside not being visible in FIG. 9b. In this case,a groove nut 61 is positioned in the miter-formed corner region of theundercuts 57 a,b.

[0126] This makes it possible for a third profile section 50 c to bepositioned flush on the main plane, from the open side of the pocket 57,at right angles to said main plane of the first two profile sections 50a,b, with the result that the outer surfaces 53 a,b of all three profilesections form a right-angled three-dimensional external corner. Thepocket 57 of the third section 50 c here is aligned with the pocket 57of one of the other two profile sections 50 a and 50 b. Additionallyrunning in this pocket 57 within the profile 50 c, and in thelongitudinal direction of the latter, is a clamping screw 62, which hasits thread screwed into the threaded bore 63 of the angle or of thegroove nut 61. The clamping screw is secured in a form-fitting manner inrelation to the profile 50 c by means of a transverse bolt 66, which isinserted into the corresponding bore in a direction transverse to theprofile and which has the clamping screw 62 passing through it.

[0127] By virtue of the clamping screw being tightened, it is not justthe case that the third profile 50 c is braced in relation to the othertwo profiles 50 a,b; the angle or the groove nut 61 is also bracedagainst the undercuts 57 a,b in the pockets 57 of the first two profiles50 a,b.

[0128] A complete corner connection is thus realized just by means of asingle clamping screw 62.

[0129] The transverse bores for the transverse bolts 66 here maypreferably be already prefabricated in all the profiles 50 a,b,c, as canbe seen on the profile 50 a.

[0130]FIG. 9c additionally shows that, when insertion panels 58 a,b arepositioned in the insertion pockets 51 a,b provided for this purpose, anEMC shield 59 is provided between the panels and groove base.

[0131] This demonstrates that, with the aid of a specifically configuredprofile from which the installation frame is formed, both adouble-walled housing with good ventilation and, or instead, a housingwith inner EMC shielding can optionally be produced very easily.

[0132] The insertion panels will preferably consist of aluminum, whichis suitable, on the one hand, EMC sealing and, on the other hand, goodconductivity for the heat developed in the interior.

[0133] The outer housing (body 3), which cannot be seen in FIGS. 9 and10, may be of an inherently stable construction or have its individualparts (rear wall, side walls, doors, etc.) fastened separately in eachcase on the installation frame 6, but with the spacing therebetween, bymeans of spacers, fastening plates, hinges or similar known components.It is even possible for the outer body to be configured from sheetmetal, if this is the express wish of a customer, despite thedisadvantageous technical and thermal effects. LIST OF DESIGNATIONS  1Distribution cabinet  2 Base box  3 Body  4 Door  5 Cover  6Installation frame  7 Top intermediate part  8 Bottom intermediate part 9 Mounting rack 10 Vertical longitudinal direction 11 False floor 12Border 13 Slots 14 Bottom cooling structure 15 Top cooling structure 16Cooling ribs 17 Functional opening 18 Functional cover 19 Heat exchanger20 Transverse direction 21 Fan 22 Air filter 23 EMC filter 24 Cablethrough-passage opening 25 Base plate 26 Main chamber 27 Functionalopening 28 Lines 29 Row of holes 30 Rib 31 False floor 32 Border 33Inlet openings 34 Transverse struts 35 Transverse struts 36 Cooling ribs37 Drive 38 Impeller 39 Blade 40 Axis 50 Profile sections 51a, bInsertion pockets 52a, b Insertion directions 53a, b Outer surface 54External corner 55 Hollow chamber 56a, b Recess 57 Pocket 57a, bUndercuts 58a, b Insertion panel 59 EMC seal 60 Inner body 61 Groove nut62 Clamping screw 63 Threaded bore 64 Charge 66 Transverse bolt

1. A distribution cabinet (1) for accommodating weak-currentdistribution installations, in particular for arranging outdoors, havinga base box (2), an outer cabinet body (3) with at least one door (4), acabinet cover (5), and an inner installation frame (6), characterized inthat the installation frame (6) is made up of profile sections (50), ofwhich the cross-sectional shapes has two insertion pockets (51 a,b), ofwhich the insertion directions (52 a,b) run at right angles to oneanother.
 2. The distribution cabinet as claimed in claim (1),characterized in that outer surfaces (53 a,b) of the profile (50), saidouter surfaces running parallel to the insertion directions (52 a,b),are planar and continuous and merge one into the other in the externalcorner (54).
 3. The distribution cabinet as claimed in one of thepreceding claims, characterized in that, on the inside of the externalcorner (54), the profile (50) has a hollow chamber (55) which iscontinuous, as seen in cross section, and has at least one groove-likerecess (56 a,b).
 4. The distribution cabinet as claimed in one of thepreceding claims, characterized in that, on an outer surface which isdirected away from the outer surfaces (53 a,b), the profile has afurther open pocket (57) in the form of an undercut groove, of which theinsertion direction is, in particular, parallel to one of the insertionpockets (e.g. 51 a), and in particular the undercuts (57 a,b) arearranged on both sides, in particular in a centrally symmetrical manner,in the flanks of the pocket (57).
 5. The distribution cabinet as claimedin one of the preceding claims, characterized in that correspondinglydimensioned insertion panels (58) are inserted in the insertion pockets(51 a,b) of the profile sections (50), which are assembled to form theinstallation frame (6), with the result that the installation frame (6)completed therewith forms an inner body (60) which, to the greatestextent, is closed apart from the door side.
 6. The distribution cabinetas claimed in one of the preceding claims, characterized in that theinsertion panels (58 a,b) consist of EMC-shielding material, inparticular sheet steel or sheet aluminum, and in each case one EMC seal(59) is arranged in particular between the insertion panels (58 a,b) andthe base of the insertion pockets (51 a,b).
 7. The distribution cabinetas claimed in one of the preceding claims, characterized in that, in thecase of a three-dimensional corner connection of three profile sections(50 a,b,c), two profile sections (50 a,b) are mitered and positioned oneagainst the other, and connected by means of a groove nut (61) or of anangle positioned in the undercuts (57 a,b) and clamped there, and thethird profile section (50 c) is positioned flush on said cornerconnection and screwed thereto by means of a clamping screw (62), theclamping screw (62) being screwed into a threaded bore (63) made in thecorner of the angle or of the groove nut (61).
 8. The distributioncabinet as claimed in one of the preceding claims, characterized in thatremaining between the inner body (60) and the outer cabinet body (3) isan air space which is open in the top and bottom regions, in particularin the direction of the surroundings, and serves for air to rise andthus heat to be dissipated from the inside of the outer cabinet body(3).
 9. The distribution cabinet as claimed in one of the precedingclaims, characterized in that the distribution cabinet (1) has a topintermediate part (7) which is arranged between the top border (3) ofthe body (3) and the cover (5), and in particular at least the bodyand/or the base box (2) and/or the cover (5) and/or the at least onedoor (4) consist of plastic and are produced, in particular, as aplastic injection molding.
 10. The distribution cabinet as claimed inclaim 9, characterized in that the installation frame (6) is arranged,in the interior of the body (3), for accommodating electricalsubassemblies, and in particular the installation frame (6), as seen inthe transverse direction, does not have any undercuts with the body (3),with the result that it is possible for the body (3) to be raised off inthe upward direction despite the installation frame (6) with all thecomponents fastened thereon remaining on the base box (2).
 11. Thedistribution cabinet as claimed in claim 9 or 10, characterized in thata frame-like mounting rack (9) for fastening the electricalsubassemblies is arranged in a horizontally displaceable manner alongthe installation frame (6).
 12. An assembly kit for producing adistribution cabinet which serves for accommodating weak-currentdistribution installations and is to be set up in particular outdoors,having a base box (2), an outer cabinet body (2) with at least one door(4), a cabinet cover (5), in particular made of plastic, in particularpolycarbonate, and an installation frame (6) for arranging within theouter cabinet body (3), characterized in that the cabinet body (6) canbe made up of profile sections (50), which each have at least twoinsertion pockets (51 a,b) which extend away from one another at anangle, and of at least one insertion panel (58 a,b), for insertion intothe insertion pockets (51 a,b) of the profile sections (50).
 13. Theassembly kit as claimed in claim 12, characterized in that the insertionpanel (58 a,b) is dimensioned such that, together with the installationframe (6), it forms at least one continuous outer surface as innerhousing.
 14. The assembly kit as claimed in claim 12 or 13,characterized in that the assembly kit comprises at least one additionalpart which can be arranged on the body (3), and in particular theadditional part is a top intermediate part (7) which can be arrangedbetween the top border of the body (3) and the cover (5).
 15. Theassembly kit or distribution cabinet as claimed in one of the precedingclaims, characterized in that the profile (50) has a cross section whichis constant in the longitudinal direction.
 16. The distribution cabinetor assembly kit as claimed in one of the preceding claims, characterizedin that the additional part is an installation frame (6) which isarranged in the interior of the body (3) and is intended foraccommodating electrical subassemblies, and in particular theinstallation frame (6), as seen in the transverse direction, does nothave any undercuts with the body (3), with the result that it ispossible for the body (3) to be raised off in the upward directiondespite the installation frame (6) with all the components fastenedthereon remaining on the base box (2).
 17. The distribution cabinet orassembly kit as claimed in one of the preceding claims, characterized inthat the distribution cabinet (1) has a bottom intermediate part (8)which is arranged between the bottom border of the installation frame(6) and the top border of the base box (2), and in particular the topintermediate part (7) and/or the bottom intermediate part (8)consist/consists of a material which inhibits electromagnetic radiation,in particular of aluminum.
 18. The distribution cabinet or assembly kitas claimed in one of the preceding claims, characterized in that the topintermediate part (7) has at least one false floor (11) and an inparticular vertically upright border (12) running all the way round thesides and, with the body (3) and cover (5) placed in position, hasopenings, in particular slots (13), for the ambient air to flow in andout, in particular in the border (12) above the false floor (11). 19.The distribution cabinet or assembly kit as claimed in one of thepreceding claims, characterized in that arranged on the false floor(11), in close abutment against the latter, is at least one bottomcooling structure (14), which projects downward, in the direction of thebody (3), and has a large surface area, in particular with cooling ribs(16), made of a material with good thermal conductivity, in particularof aluminum, and arranged in particular at the same location as thebottom cooling body (14), but on the top side of the false floor (11),in close abutment against the false floor, is a top cooling body (15),which consists of a material with good conductivity, in particularaluminum, and has a large surface area, in particular cooling ribs, andin particular is identical to the bottom cooling body (14), and inparticular the cooling ribs (16) of the top and/or bottom cooling body(15) or (14), respectively, run in the horizontal transverse direction(20) of the distribution cabinet (1).
 20. The distribution cabinet orassembly kit as claimed in one of the preceding claims, characterized inthat the cooling ribs (16) of the top and/or bottom cooling body (15) or(14), respectively, run radially, as seen in plan view, and in thecentral region, in particular centrally in relation to the geometricalpoint of contact with the cooling ribs (16), an impeller (38), inparticular a radial-flow impeller with blades (39), which are bent inplan view in particular, is arranged in a state in which it is mountedsuch that it can be rotated about an in particular vertically uprightaxis (40), and in particular the cooling bodies (14) and (15) extendover more than half the basic surface area of the top intermediate part(7).
 21. The distribution cabinet or assembly kit as claimed in one ofthe preceding claims, characterized in that the slots (13) at thetransition between the top intermediate part (7) and the cover (5) areproduced, by the cover being placed in position, in that, in thisregion, the border (12) is set back inward in certain sections inrelation to the cover (5) positioned thereon, and the resulting slots(13′) are overlapped in the horizontal direction by the cover (5). 22.The distribution cabinet or assembly kit as claimed in one of thepreceding claims, characterized in that arranged in the false floor (11)is a functional opening (17), for the insertion of a multiplicity offunctional parts, for example an automatically closable functional cover(18), heat exchanger (19), fan (21), with air filter (22) and EMC filter(23), and in particular the false floor (31) has a plurality of cablethrough-passage openings distributed over its surface.
 23. Thedistribution cabinet or assembly kit as claimed in one of the precedingclaims, characterized in that the bottom intermediate part (8) is oftray-like design and has a false floor (31), a peripheral body (32) and,in particular, air-outlet openings (33), and in particular the falsefloor (31) of the bottom intermediate part (8) has a functional opening(27), for fastening a multiplicity of functional elements therein, andin particular the false floor (31) is arranged in the bottom heightregion of the border (32).
 24. The distribution cabinet or assembly kitas claimed in one of the preceding claims, characterized in that theoutlet openings (33) in the border (32), which is open at the bottom,are produced by the bottom intermediate part (8) being positioned on thebase box (2), in that the top border of the base box (2) is set backinward at least partially in the radial direction in relation to thebottom border of the bottom intermediate part (8).
 25. The distributioncabinet or assembly kit as claimed in one of the preceding claims,characterized in that the distribution cabinet (1) has EMC shielding, inrelation to the main chamber in the interior of the body (3), and inparticular the EMC shielding is provided in the body (3) or on the innersurfaces of the body (3) or on the outer surfaces of the installationframe (6) and, in addition, the top and bottom horizontal surfaces ofthe body (3) are shielded, and in particular the top horizontalshielding is effected by the top intermediate part (7) and/or the bottomhorizontal shielding is effected by the bottom intermediate part (8),and in particular the bottom horizontal EMC shielding is effected by abase plate (25) made of a material which shields electromagneticradiation and is fastened, in particular, on the body (3), and inparticular the EMC shielding consists of a material addition to theplastic of the body, of a coating of the inner surfaces of the body orof a woven fabric or of metal sheets, in particular perforated metalsheets, which are fitted, in particular, on the outsides of theinstallation frame (6) and/or the insides of the body (3) or of the door(4), and use is made here in each case of materials which inhibitelectromagnetic radiation, in particular metals.